D.B.
Hi,
My step-son lost his mom to bad life choices at age three, pretty close to your daughter's time of loss. I know how hard it is, and I know the repercussions it can have. You're right to be concerned and your concerns are spot on - inconsistency will be the most hurtful thing there is.
First, as mentioned, get your legal ducks in a row -- NOW. There is no greater priority. Do it by any means necessary, just do it. Trust me.
Second, start laying the groundwork for your future and (gradually) for her mental preparedness:
1) teach her that your love is unwavering, all inclusive, unconditional and proactive. Prove it daily, say it daily.
2) Prove to her daily that you never make a promise without keeping it. You have to be the one person in her life she can trust implicitly to DO what she SAYS she'll do -- believe me when I say that in the future, this will be her lifeline.
3) Give her structure, consistency, routines and safe, loving rituals (like songs at bedtime, little tea-party "confidante" sessions, whatever suits). Keep them regular, so that if she outgrows one there are still two in place while you phase in a new one. Honest, these little routines and rituals will seem frivolous now, but when the missed visits, forgotten birthdays or 'dad's hungover and can't come' calls arrive, those rituals and routines will spell survival to her little psyche.
4) Begin teaching the fundamentals of personal safety, personal space and what kind of touching is allowed. She needs to have a solid, confident understanding of herself and her rights by the time paternal visitation becomes an issue -- not necessarily because of him, but because of whoever might be associating with him, even people stopping by.
5) Begin teaching her the basics of how to get help if she needs it: who to call, how to dial, how to find help if there's no phone -- and this sounds crazy but -- implement a "SAFE WORD" with her that is JUST between you and her. Start the Safe Word now. Get her used to using it before she truly needs it. That way, if there is ever a time when things have gone sour and she's far from home, she can mention her Safe Word in conversation to you and she won't be afraid. Because it's code, no one will know she's asking for help -- Just you, the one she knows she can always trust.
6) Begin reading child psychology books right now, don't wait for the problems to manifest -- that's the thing I wish I'd done sooner. The level of deep-seated anger that took hold of our son (my step-son, technically) was mind-blowing. I wish I'd been better prepared. Looking back, I should have had him in counseling years earlier than we did. You have to understand that this sort of rejection -- even if it's only perceived rejection -- poisons so many facets of a little personality.
7) Start developing a thick skin if you don't already have one. When the anger, resentment, confusion, the sense of loss begin to hit her on different levels, you'll be the whipping boy. No way around it, that's what we're here for. We have to be safe enough and strong enough for them to let it out. And it ain't pretty. When she's about 8, that's when it gets personal. DON'T coddle her at any age. DO understand where it may be rooted and work accordingly.
You'd get some 'independence' or 'rebellion' regardless of childhood trauma -- around 8 is when they 'come into their own.' But when there's a missing parent, one who's betrayed the child on some level, BOY do those of us who 'stood fast' take a beating. It's ok, it's normal, it WILL get better. This is the point at which, if she hasn't already had it, you need to get her counseling asap. And stand fast, despite the tempest. She'll thank you a few years later. (Just got my first "Thank you" this year. Yay!)
That's all I can think of for now, but it's such a big issue that I know there are volumes more to say. Look for support groups in your area, as well, that may give you some insight, support, good ideas. And hang in there. The fact that you've already identified the potential pitfalls puts you miles ahead of the game. Now go find a lawyer! :-)
Best of luck in all of this. :-)