This study includes a longitudinal mixed methods study of 360 YYA with diabetes in SC, CO, and WA conducted with SFS 1 participants. SFS 2 will have two parts: (1) an intense, longitudinal study consisting of two 14-day assessment periods spaced 9 months apart which will include CGM, EMA, accelerometry, and surveys in all participants (the EMA study); and (2) a concurrent events qualitative study with a subset of participants (30 T1D, 15 T2D) who will complete 13 one-on-one, semi-structured interviews throughout the 9-month assessment period (the qualitative study).