There are some indications that maybe something is happening there. So it's again only an recording for the enthusiasts of you, who like to search for something meaningful in a recording. I thought that maybe some of you would have fun with it.
I cleaned up & enhanced the recording as best as I could. But there is still a lot of russian music and the dog is running around.
What I could hear:
younger sister:
0:16 - Oh ja (Oh yes)
0:53 - Moan
1:19 - Second moan
After this they are no big moans again. So I'm not even sure if something sexual is going on or not. Therefore let's hear your opinion