How often would the Autobots nom their kids?
I think Jack would be too big for her but Arcee would do it out of overprotectiveness mostly? I can't really see her doing it for anything else.
Bumblebee and Raf would like the closeness of it obviously. Perhaps they just chill out?
Miko is an active tank hazard and she probably harassed Bulkhead into swallowing her the first time.
It all depends on how kids are and what is happening
So the thing is humans are small and fragile, all bots know that, but having kids under your care - it will drive anybody crazy, especially when it have been centuries since anyone seen a sparkling. So having children of somewhat same looking species actively rely on you for safety means a lot, and that sire/carrier protocol would be sudenly activated and it be game over for kids.
We can see Bulkhead already freat over Miko with parental instincts, so imagine how bad it will be now that they know thay can just stuff the kids inside them. Miko is the most out of three to be in Bulkheads gut as she is accident prone and it is easier to keep her out of trouble when she is inside you. The first time Bulkhead nommed her, he was actually worried that the kid would be scared - nope, she just kicked back and chilled.
Yes, it is more difficult for Arcee to stuff Jack in to her, yet the PTSD of lozing her partners to Arachnid and now Starscream realy made her sort of ignore the size and just stuff her self. When she does do it, it greatly reduces her mobility and most of time you will find her in her room, chilling. It is even worse when she sees him covered in bruises after another Vince desides her charge is good enough of punching bag to let his pent up anger on or when Jack stands up for someone the red head was bullying. She is seriously considering teaching Jack how to kick ass.