OP, I'm glad you are getting legal status and some support through DCF. Hopefully Medicaid too?
With strangers and a nonverbal child, I'd probably stick with "foster baby." If they press you to find out if you're hoping to adopt, then 1) they're being rude and 2) you can tell them whatever you'd like.
Nobody needs to know that your sister is a meth head, except those that already know. It's not that you're obliged to keep her secret - far from it. You owe her nothing. It's just that it's not really relevant in most situations that your foster baby is also your bio nephew. It doesn't provide people with useful information about the situation, except your family and close friends who are helping you deal with the tangled mess that is kinship care.
When he learns to talk, he'll call you "Mama," which is exactly what he would do if you shared no DNA.
Foster baby really does seem like the most comfortable for me, I appreciate your opinion, Smithie. Knowing the situation makes my husband and I very sure that there's no possible way that she will be interested enough, nor able to pull herself together to do what she needs to do. So my husband (as well as everyone else involved, including her) is perfectly comfortable moving into "son," but foster son feels more like a good transition and acknowledgement that there's clearly still the possibility of the situation being temporary.
He's just started calling us mama and dadda (though doesn't recognize which means which yet, just that one of us pays attention to him when he says it), and I couldn't help but wonder how a foster parent would deal with this period of development.
My husband tells me that it's not our decision whether he's with us for the next 18 days, or the next 18 years, that forever long we are blessed with him we are his parents, and therefore he is our son, even if temporarily. He seems to be much more comfortable embracing the moment, even if it means in a month or twelve, we have to adjust to a different type of relationship...
So much confusion with the situation, but by calling him our nephew it's lead to so many uncomfortable questions or has felt like our relationship with him is dismissed because he must just be visiting, when he's nothing of the sort.
One day at a time. :)
He has medicaid already, thankfully. First doctors appointment and shots the 26th! We also were offered coordinated childcare for him, but thankfully don't have much of a need for it with the types of work schedules we have. We could change our schedules to be able to take advantage of the CCC but it would mean less time with him, so I doubt I will go that route he needs as much one on one attention as we can afford.
Most foster babies start calling their foster parents whatever the other kids in the house do. Some people choose not to attach meaning behind the "ma ma ma ma" sounds but most do and it's perfectly fine. You are the mother of your house.
One thing this made me wonder is that by calling him nephew, other people automatically think they have a right to information about your adult relative (can't remember if it is your sister or your partner's) and why this person is screwing up and how that relates to you both as individuals. So in a way they get too much information simply by knowing his biological relationship to you. For some people, this alone would provoke a sense of shame--- they'd feel they had to explain why the child's mother (their sister/brother/etc.) was so messed up and family background, etc. Not sure if this is making sense, just having my first cup of coffee!
It's true, there's a considerable amount of shame involved, and I'm not sure if it's because of the way people react, or the way I feel about it.
I wasn't raised with my sister, so there's really no connection between us other than we share the same mother (again, not really raised with the same one though).
There are no other children, so the only lead he can follow is what we give him, which is part of what makes this complicated, but more than that - what everyone else has said, how simply just saying that he's our nephew gives more information than we are comfortable giving to people we've just met - which seems to be a heck of a lot since babies seem to be people magnets!
Thanks for everyone's input. :)