"AITA for following up on DNA report?"

I (53M) was born prior to my parents getting married, and am the oldest of four. I have 3 younger sisters. My dad passed away a couple years ago. My mother is in poor health (multiple bypasses, recent stroke, depression), and recently moved in with sister #2.

Last week, 23andMe informed me that I had two half sisters. My dad had at least one affair that we knew about in the 90s, so my sisters and I initially thought that these two girls may be the product of an earlier affair when we lived in the area the two girls are from.

After questioning the two potential half sisters about their family history, I found out that they had already confirmed 100% DNA match with both of their parents six years ago. I was told that I resembled their brother. All three of my sisters told me the DNA results were wrong. I was my dad’s son. They urged me to not pursue the issue, and told me not to bring this up to my mother.

The elder of the potential sisters and I wanted to unravel the mystery, since 23andMe was telling them I was their uncle. Eventually, an exchange of photographs hit me hard. I look exactly like their biological father. I showed the photograph to sister #3, who showed it to sister #1. They changed their minds and told me that I need to find out the truth.

My problem is this, the biological father of the potential half sister passed away 11 months before my Dad. There are two people I can ask about this and hopefully get an answer: my mother, and her younger sister. One I am forbidden to question, the other would cause a massive s-storm in both families if given the opportunity. Sister #2 refuses to speak to me. AITA for wanting to confront my mother on my paternity?

What do you think? AITA? This is what top commenters had to say:

HellaShelle said:

NTA. But can’t you just test with both sets of sisters? That way, if you don’t want to bring your mom or aunt into it, then you wouldn’t have to.

[deleted] said:

I uncovered my real biodad back in 2019, 2020 was when I met him, 2021 is the year I found out some horrible truths about him. Now I'm not sure how to cope with everything but am building a relationship with my half siblings. My mom shuts down whenever I bring it up so I don't tell her when I visit my half siblings. Anyway, make sure you are prepared for the emotional breakdowns it can occur.

And Future-Ambition1859 said:

NTA. You're entitled to know your parentage. Speak to your mother. Don't accuse, just let her know that all you want is the truth.

He later shared this first update:

Shortly after I posted this, sister #3 (48f) submitted her DNA to 23 and Me, she came up as my half sister. With this info, Sisters 1 & 2 (52f and 50f) decided that I should speak with our mother to get answers. Sister 2, however, confronted my mother before giving me the chance to ask the questions I wanted to in the manner I had planned to.

Our mother denied knowing my bio father. My mother and I did not speak to one another until July of this year. I have been in contact with paternal sister #1, exchanging photos and stories of family life.

And then, he shared this second update:

My mother arrived for my niece’s wedding. On July 4th, I received a phone call from sister #3 telling me to come up the driveway to my niece’s house, as our mother had something to tell me. After driving the mile up the driveway, I got the full story from my mother. Long story short, I am the result of an assault from someone from my mother’s workplace.

I was legally adopted by my Dad 6 months after my birth. I was very much wanted and loved by both of my parents. In fact, my dad was angry that he had to wait 6 months to adopt me and have my birth certificate changed. I have not updated my paternal siblings yet.