C was a very easy infant when it came to sleep. She STTN very early on with only 1 wakeup. We used CIO at 6 months to swaddle wean her, after which she started sleeping 12-14 hours straight through every night. We hit a rough patch 8-10 months due to international travel and general issues but we were back on track at 10 months old, STTN as usual. Some nights she would cry a bit before sleeping, but most times she would talk herself to sleep quietly and go down fairly easily.

These issues started when she turned 1. She started fighting her afternoon nap HARD, so we went to 1 nap. Her schedule looks roughly like this:

8am- Wakeup
1-3/3:30- Nap
7/7:30- Bedtime

THEN she started sleeping in a lot. She got sick and started sleeping in until 9 or even 10am. After that, she started fighting bedtime, which is the current HUGE issue we're facing. She has turned into a massive, horrible sleep fighter. She always fought naps hard, but never bedtime. Now it's opposite.

She will stay up for up to 2 hours after bedtime, sometimes talking, sometimes playing, sometimes crying. At first, we just let her go, thinking she would get the memo and stop staying up like that. No dice. Then, we tried going in and laying her back down and leaving. Sort of worked. Things improved a tiny bit. Then she progressed to throwing full-on fits before bedtime. So, my husband started going in and picking her up to calm her down and then putting her down.

I just got done fighting her for 2 hours and Im not totally sure she's even asleep now, she's just not screaming anymore. Today, she woke up at 8:30, took 1 nap from 1-3:15 and then we put her down at 6:45 because she was yawning, rubbing her eyes and cranky. She screamed until 8:30 when I went in for a 2nd time, picked her up and then gave her some milk. I think she might be asleep now.

Im so done. I thought at first it was teeth. She has sprouted 6 teeth in the past 3 months and is working on the last 2 molars as we speak. Im not so sure thats the issue now.

I dont know what to do and I cant go on like this. I feel like my husband and I have effed everything up royally by going in and picking her up. Ive come to suspect that she waits for us to come in before going to sleep now. Once she's asleep, it's all good and she's out like a light for 12 hours. It's just the getting her to go to sleep that's torture.

Advice?