Holly is also pregnant.

As I wake up next to a naked Jane, I hear someone at my bedroom door knocking. I get up but don't unlock it.
"Who is it?" I ask.
"Me," my dad replies. "Just want you to keep it down next time."
I blush, and go back to bed without saying a word. Jane is lying face down. She truly is beautiful. I admire her firm and perky ass and lie on top of her so my dick is resting on her anus. I don't put too much weight on her because I don't want to hurt her.
The doorbell rings, waking Jane. She turns around, smiles at me, and gives me a quick kiss on the lips, without saying a word.
I throw some clothes on, and I'm pleasantly surprised to see Holly at the door.
"Hey!" I say, but then I realize she looks nervous.
Before I can say anything Jane bounds down the stairs, having seen who it is, in just her dirty underwear from the night before.
"Hi Holly! Good to see you again!". Jane pulls her in for a hug, and they share a short kiss, clearly comfortable with each other and the situation around us.
Jane doesn't bother to put any clothes on, and the rest of my family has left the house, so we are alone.
Sitting on the couch, Holly speaks up, clearly on the verge of tears, though she tries to hide it. "I have something to tell you... I know you only came in my pussy once, but.... I'm pregnant."
Wow, I thought. I must have some strong swimmers. I look over to Jane who is clearly thinking about what this could mean. Eventually she smiles, then leans in and says in my ear, "do you think you could leave us two alone for a bit? We should talk. It'll be fine, I promise."
So I left the room. I returned after 10 minutes.