My 2.5 year old niece is she being abused?

[freedom86]

I'm going to try and do this in a very short form stating facts.
My niece 2 year 10 months old.
My gf and I are very close to her we helped since day one she is our world.
We have a Good relationship with my sis and her boyfriend parents to my niece.
We all have lived together since she was born.

Niece was 1.5 years old when I came home early to see bathroom door shut and baby making sexual sounds with her dad.i banged on door said what the hell are u doing he hesitated for a couple mins then came out sweating and a red face walked past me and I took the baby. He said he was going number two. And that was that. I know what I heard wasn't normal.
Nothing was said.
That same night we all were attending a event but meeting g at diff times so my gf and I took the baby drove to meet them. She was sleeping in my car and my sis bf was in the car too apparently. My sis went out and they got u to one sort of argument. They ended up leaving with my niece to go home. My dad was came up to me before he was leaving and Sid my sis said to him her bf may be touching the baby I went to tell my gf and immediatly called a cab to go to the house. I walked in said what was said to my dad and my sis clled me crazy.again "nothing happens".. We moved out got our own place time went by and m niece came to our new house for a sleepover. She was really quiet and exhausted bags under her eyes and fighting changing her diaper. I was like we are changing you diaper and I took it off and she had a massive rash. I said baby are you ok and she started touching herself and said Daddy... She did this about 4 more times while at our place.i told my sis what I observed and she basically disowned us.
Saying I was sitting sick.
Couldn't believe it.
"Nothing done"
Time goes by he taking baby on outings from 5 pm to 1200 am always late and even when she would cry no I don't want to go but they would go.this was now every day he was doing this. My sis takes it as a break for alone time I look at it as she is 2 what is he doing it's her all this time.
She is petrified to go near toilets, he can't bathe her, she doesn't kiss anyone on the lips but he makes her no matter what. He won't leave it alone until she does.
Time goes by to now just a couple weeks ago we took her to my dad's my gf and I and she was staying for the weekend. She was acting real scared wouldn't sleeping her crib and begged to sleep with my gf and i. My dad her Grandpa came to the door at one point and she had so much fear. We let her in the bed she fell asleep and we we're watching her sit up grind her teeth and sleep talk in a full sitting up position all night.she was a different baby again now worse. She said to my gf that she is scared of the monster who comes into her room and pinches her every morning and the monster lives in moms room.so I bought a voice recorder and put it in her room when we dropped he off after the weekend.istend to the tape after it was recording two days and could hear sis saying k I'll get Daddy to say goodnight she was crying and said don't come back to my sis. Sis leaves, you hear door open and close h comes in and all of a sudden you hear for about 15 mins excessive sex sounds coing from her again.very distinctive. He in and out on that recoding for 8 hours. He called into work next day fishy to me maybe cuz he was up al night. Is happens a Second time in the recording ."same sounds". Showed my sister the recording and she again said we r crazy. My niece has trouble pooing, refuses to let you see her naked, has nightmares, doesn't eat, always is sick, won't go for baths, won't go near toilets, loves my sister until he is around she is emotional, acts out, if you still Daddy she panics, never goes to him only when he grabs her and doesn't let her go. My nice protected my gf and I when shey sis was acting ridiculous saying in front of her we are crazy she said no mom Daddy comes in room and hurts me. What should I do I mean I know what I should have already done I feel like I'm second guessing what I hear,know and feel. I need some advice. My sister is being manipulated by him and he is a liar and she doesn't want to ever think he would do that. Nobody will listen o the recording to know it's happening. Need some help and guidance.

[RockRose]

THIS IS REALLY LONG.  The concerning thing is the recording that sounds like sex.  You need to call CPS and give that to them,  and don't tell the entire very very long story except to say you suspect child abuse and you recorded this,  and give their names and address.