I am "auntie chris" to my son's 5 year old. today, as his mom and I were discussing how to come out to me he came running up to me, gave me a huge hug and randomly called me "chrissy". have no idea where he pulled that from. it was kind of funny but confirms it's time to tell him. so, what do you say. he's a good kid but he's young for his age. we don't think it will upset him but we are just trying to find language he understands.

any advice?

My therapist always said... The easiest people to tell are young children. They don't have preconceived ideas and generally accept things. Aunt Chrissie is correct... You are a woman hiding in a man for a while. Most likely he will say "of course"...

The only issue with telling young children is they can't be relied upon to not tell others. They will be dying to tell their friends if there is a "big secret...". Play it cool and simple and you will be surprised.

When I told my 4 year old son and my 7 year old daughter things went pretty smoothly actually. You'd be surprised how adaptive and understanding little children are. My kids were the first to change over to my new name and pronouns, the quickest to correct themselves. It actually blew my mind how quickly they went with everything.

I was recommended by a ftm group on livejournal about this book which I bought and read to my kids and it really did help a lot. https://www.smashwords.com/books/view/274343#download

I think just sticking with the basics, and having the people around them reinforce pronouns/name is a big factor. I'm sure things will go smoothly and just beware kids are super curious, they will ask weird and even embarrassing questions, don't shy away from that and don't put them down either. They don't know it's wrong to ask certain things. If it's all answered in a positive environment then it should be ok.

Okay first bad joke but it does back up what monkeymel said. 
"The two things a child can't keep to themselves?  Infectious diseases and their mothers age" So once you tell him if you are not completely out stress it is a secret and not to tell anyone,  he may slip up but. .... Pending on the age and the environment they are raised in kids can be fairly accepting with what goes on around them.  Also you may be surprised kids are also perceptive he may already know something is going on just not what

I'm going to try to take and run with this.  I've been thinking about how to tell my daughters (step-10, 4, 2.5) exactly whats going on, but its been kind of difficult.  The oldest one knows I wear women's clothes, and when my wife started to talk to her about it, the 10 yr old (just turned 10 today!, Holy Cow!) said something along the lines of "it's okay, girls clothes are so much prettier, softer and more comfy than boys clothes anyway.  I understand."  It blew my wife (and I when I was told of this) away.

The main problem is I don't live with them.  My jobs are here in S. FL and they live in RI (I had to get them out from down here, horrible place to raise a family, and the job market in RI is nearly nonexistent).  I get to Skype with them on occassion, and talk on the phone, but it's not enough.

Thanks so much. Yeah, I was planning to keep it simple and I'm ready for questions. I work with kids so I know they come up with all kinds of crazy stuff. I may get the book even though I'm not a parent. After we get done with it I can pass it on to someone who needs it

I also have no expectations he will keep it secret. He's a kid. I would never ask a kid to keep a secret and if he blurts it out someplace unexpected, than so be it.

He's such a goofy kid, this should be interesting

I am worried about this with my 3 yr old daughter.  I am out only at home so just my daughter and girlfriend (we may as well be married) have seen me female.  Sometimes my daughter asks why I am wearing that, but slow immersion seems to have made her indifferent to it.  This indifference was the goal here for me, if it's no big deal to her it's probably not worth talking about at daycare or around my parents or friends.  She seemed more traumatized when I shaved the beard!

Telling J went great. We got the book that Hex recommended. Read it to J. Told him about me. He asked to hear the book again. Read it again. He said "so your a boy now?". yep. "so I say he now" yep. And he got it.

I want to share the book with a friend if she wants it but after that I will happily mail it to someone. Just PM me if you want it.

I'm so glad the book helped Christopher! Even better things went great with J!