To what degree should a person need to confess sins that they committed due to immaturity as a child? I’m always remembering small things I did years and years ago and feel like I need to go back to confession even though I had no idea that it was wrong or right at the time. Some examples include sexual curiosity with friends or letting a pet lick you in the… nether-regions. I wouldn’t want it to sound like I’m actively involved in pedophelia or beastiality… I wasn’t developed in faith much at the time.
There’s a lot of factors in answering this question.
How old were you?
Was this just one-off experimentation or a habit?
Were you already aware of the sinfulness of sexual sins at the time of the sin?
I’m guessing that at that age you almost definitely didn’t commit a mortal sin because of either not full knowledge of the sin or not full consent (very young.) However, if you believe there could have been some serious sins back there, you can clear it up by just going to confession and confessing that you remember sexual shenanigans when you were very young, and giving all the important details you can. Just be sure to say that you have only recently remembered these things so that the priest does not think you have been holding back this sin all this time, or something strange like that.