Read Dragonball AS- Argula's Story :: DBAS Extra2: Full and Half-Saiyans Headcanons

Full Saiyans:

Full Saiyans as kids stay in tiny kid bodies up until age 18. (Think back to kid Goku in OG Dragonball, he stays a tiny kid up until the tournament against Piccolo/Piccolo Jr. and he had an adult body all of a sudden)

(i.E: Goku, Vegeta, Argula, Escaro, Toka, Piyano, Matiloto etc. would stay kids far longer given how saiyan biology works and the fact that thy age slower)

Half-Saiyans:

Half Saiyans still grow up slower like full saiyans do and relatively stay in little kid bodies up until age 11 (think Teen Gohan in Cell Saga)

Also, they all will randomly get rage boosts (much like Gohan did from Saiyan Saga thru the Frieza one)

(I.E: Goten, Trunks, Bra, Sano etc would be able to use these at random times)

1/4 Saiyans:

Would more than likely age up like a human/earthling (given their only 75% Human/25% saiyan like Pan, and would have a much harder time as well going SSJ)