Holden's playdates

I'm at a friends babysitting and Holden and her daughter Lucy (who Holden adores) are playing. Holden says "lets pretend that I love you and you're my girlfriend and I'm your boyfriend". Lucy says "okay", then he hinds behind the coach and says "I'll text you that". Then they go one playing and a little bit later I hear Holden say, "Okay now let's pretend that I have another girlfriend and her name is Jen and you're okay with that". Lucy says, "OooKaaayy" and then she says, "text me that too".

I don't know who I should be more concerned with in this scenario. I'm surprised that Lucy went along with it in the first place because since Holden confessed his love for her 2 1/2 years ago she's told us she's not committing to anyone just yet. She's a catch. I don't blame her.