[listen, none of this is canon so it's the fan version of what the canon is]

Tippy's mother [Tracy]: Disappeared when Tippy was barely one to escape her abusive marriage with Fendrich.

Tippy's biological father [Michel]: Died in a car crash caused by Fendrich.

R.E Fendrich: stepfather.  Manipulated Tippy's mother to marry him so she could have her child (Tippy).

Tread Octane: Former schoolmates in elementary school before Tippy was taken out of school from being harassed.

Harl Hubbs: Close friend turned Boyfriend.

(( this is it so far he doesn't have any other personal connection to anyone in the Tippy lore so if you have any suggestions on who else to add please comment))