The purpose of this study is to learn how well a new mobile app helps families manage their child's nephrotic syndrome. We will be asking what parents think of the new app and how we can improve the design of the app. We will look for 60 parents to participate in the study, from 4 children's kidney clinics in the United States. The study will last 12 months. Participants will be asked to check their child's urine protein levels at home daily and answer surveys. If participants are randomly assigned to the mobile app study arm, they will be asked to use the app. The risks associated with participating in this study include loss of privacy and breach of confidentiality. There are no anticipated benefits to your child from participating in the study, but we hope that in the future the app will help families manage nephrotic syndrome. The alternative is to not participate in this study. Participants will be compensated for their participation in the study.

This study is for patients that have had hematopoietic stem cell transplants and/or have been donors. The purpose of this study is to see how well transplant works in adults with a MMUD using stem cells from a donor's blood, and in children with a MMUD using stem cells from a donor's bone marrow.This study treatment does not include any investigational drugs. The medicines and procedures in this study are standard for transplant. Participants can expect to be on this study for approximately 1 year.

Learning new words is challenging for all toddlers, and it may be particularly challenging for toddlers who are late talkers. In this study, we ask whether late talkers use the same cues to figure out the meanings of new words as do their typically developing peers. Toddlers ages 2.0-2.5 will watch videos of people doing new actions and hear made-up words. An eye-tracking device will capture their face and their gaze patterns, and we will use this data to determine how they are making sense of the new words they are hearing. Results will provide insights into how toddlers learn new words and whether this process relates to toddlers' current language abilities.

This research study aims to learn more about children and adolescents who have a shiga toxin-producing E. coli (STEC) infection. E. coli is a type of bacteria found in the intestines. Although most types of E. coli are harmless, some produce toxins that can make children sick. This study will assess what type of treatment is best for this infection.

This study is for patients that have been diagnosed with leukemia. This study is called a screening study and we are doing this study to find better ways to diagnose and treat leukemia in children, adolescents and young adults. Bone marrow, blood, and medical information about participant's cancer and treatment will be collected. Participants can expect to be on this study for 5 years.

This study is for patients that have been diagnosed with non-germinomatous germ cell tumor (NGGCT). The goal of this study is to see if radiation therapy (RT) to the spine and a portion of the brain works just as well as the standard treatment, which includes RT to the whole brain and spine, for people with NGGCT who agree to take part in this study, and whose disease responds well to induction chemotherapy, or who have no signs of disease following surgery. Participants can expect to receive treatment on this study for about 6 to 11 months, depending on which therapy they receive. After study completion, participants will continue to be followed for up to 10 years.

This study is for newly diagnosed previously untreated neurofibromatosis type 1 (NF1) associated with low-grade glioma (LGG). The purpose of this study is to see if selumetinib works just as well as the standard treatment of carboplatin/vincristine (CV) for subjects with NF1-associated LGG, and to see if selumetinib is better than CV in improving vision in subjects with LGG of the optic pathway. Participants can expect to receive treatment for up to 24 months, until the cancer gets worse or until the side effects are too great. After study completion, participants will continue to be followed for up to 10 years.

A prospective parallel cohort study generating two groups of participants will be performed in NEPTUNE. The two groups are: (1) Cohort A which includes the FSGS/MCD Cohort; and the MN Cohort, both incipient and prevalent biopsied patients; and (2) Cohort B – a non-biopsy, treatment-naïve, pediatric cohort less than 19 years of age, cNEPTUNE. The sample size for the combined FSGS/MCD and MN Cohorts is a minimum of 800 participants, with a minimum of 375 new patients recruited under Protocol V5.0. The sample size for the second group, cNEPTUNE, will be a minimum of 200 participants. Participants will be recruited into each subgroup concurrently. All participants who meet the inclusion criteria at the participating centers will be enrolled if the participants or their legally authorized representative(s) provide comprehensive written informed consent. A recruit-to-replace strategy will be employed throughout the enrollment phase. Cohort A study visits including screening/eligibility, baseline, biopsy, and follow-up visits, and SMS texting. Study visits for Cohort B, cNEPTUNE, including screening/eligibility, baseline, follow-up visits, and SMS texting.

This study is for newly diagnosed or previously untreated low-grade glioma (LGG). The overall goal of this study is to see if selumetinib works just as well as the standard treatment using carboplatin and vincristine (called CV) for subjects with LGG. Selumetinib is a drug that works by blocking a protein (a basic building block of the human body) that lets cancer cells grow without stopping. Participants can expect to receive treatment on this study for about 1–2 years. After study completion, participants will continue to be followed for up to 10 years.

This study is for participants that have been diagnosed with Medulloblastoma. The purpose of this study is to test the effectiveness of using an investigational agent called DFMO for Medulloblastoma. An investigational drug is one that has not been approved by the U.S. Food and Drug Administration (FDA). This study will look at the ability of this study drug to either keep participants tumor in remission or if they have active tumor, for their tumor to respond to the treatment and will also look at the safety and tolerability of DFMO. After this first day participants will be seen in clinic once every 30 days for the first 6 months of the study, after that they will be seen once every 90 days for the remainder of the study. These visits will last about 2 hours.