I have a 3 yr old and and in order not to get up I ask dh to do it especially if the clock shows I don't have much time before having to temp. Not sure if that is an option for you. Or you could do OPKs and not chart BBTs but then you won't know for sure if you have indeed ovulated.
I temped while my DD was that young, and just did the best I could if I had to get up in the middle of the night. As long as you have about 3 hours of sleep before your normal temping time, your temps should be fairly accurate. There is a section here on Pregnancy.org for charting, and FertilityFriend.com is also good, they have a section there that talks about temping when you have to get up at night. Let me know if you have trouble finding it and I'll look it up for you and give you a link. HTH
I'm kind of in the same boat.
I've just been using OPKS because of course as soon as im TTC DS who is THREE gets up in the middle of the night to come sleep with me, and with Kevins alarm going off at 5 and DS up by 7, there's never a 3 hour stretch of sleep!!
If I still cant get a BFP in a few months I think I'll finally just temp- and I'll go sleep/hide in the spare room so nobody can find me
I have a four year old and a 15 month old, so I get up a lot at night, too. The best advice I can give you is to temp really early. You need at least 3 consecutive hours of sleep before temping. So if you go to bed around 10-11, set your alarm for 2 or 3 a.m. Alarm goes off, throw the thermometer in your mouth, take it out when it beeps, and check your temp in the morning. (Almost all digital thermometer save the last temp taken.) I know it sounds crazy, but once you get used to it, you don't even wake up, really.
I've done a lot of temping while BFing. Twice I've conceived while BFing a baby less than 1. Both times O was clear from the first time PP through conception even though my amount of sleep and waking times were all over the place. Give it a try and see what you get. You might be surprised. Good luck!
big boy 12.8.07 @ 39+2 7lbs 8oz, 20.5" BFed for 13 months
middle boy 8.12.09 @ 39+4 7lbs 9oz, 21" BFed for 13.5 months
little boy 4.26.11 @ 38+4 6lbs 14oz, 19.5" BFed until 26mo and again 30-37mo
baby boy 10.25.13 @ 41+0 8lbs 15oz, 21.5"
8.16.12 & 12.16.12
surprise pregnancy ended 1.9.15