I don't think little!robby would have agere gear.
I think pacis, bottles, teethers, and most toys would pull him out of it. out of the fuzzy, safe side of littlespace. too much gear would just lead to him berating himself, for needing it, for wanting it, for being a pathetic kid. it'd only end in tantrums and breakdowns.
so jack, searching for comfort objects, for anything to soothe his little one, finds two things robby can stomach without being made too self conscious or embarrassed.
1. a worn bear stuffie. it was jack's first, which greatly helps. if jack can cuddle a stuffie at night and still be strong, reliable jack, it's okay if robby does it too, right? it's soft, it still smells like jack, it's a good size to hug. it's quiet. easy. just... something to hold onto. sometimes jack sees robby nuzzle into it's soft fur, and it makes him melt. sweet boy.
2. jack's thumb. robby refuses pacis and won't suck his own finger, but in the cradle of jack's arms, sniffly and fussy, he accepts a gentle thumb pushed into his mouth. it tastes like jack, which helps. robby just needs to be surrounded by jack, needs all his senses filled with him. jack is safety. jack is comfort. so he'll latch onto the thumb, suckle til his shoulders droop, tension draining out.
nothing helps more than jack's voice. low and steady and crooning, a soft stream of praise. attaboy, that's it, just relax, kiddo. you're alright. you're okay, misha. papa's here. papa's always here. you're my good baby, you know that? my sweet boy. shh, shh, misha, papa's here, papa's got you.