Shawn Mendes opened up about reacting to and being influenced by producer Teddy Geiger’s transition.

The “Treat You Better” singer explained in an Entertainment Weekly interview published on Wednesday, May 23, how Geiger coming out to him as transgender impacted his new music. “The whole album. I made the whole album with her,” Mendes said of his longtime friend. “I met Teddy the night I cut ‘Stitches’ and we’ve had a really special connection ever since then, and for her to feel so comfortable with me and the other songwriters the night she came out … I can’t express how happy that made me.”

He continued: “And it’s something I really love to say: it’s a very new thing, right? People transitioning, there are still a lot of people who don’t understand it, and to refer to somebody as a pronoun that you haven’t been referring to them as their entire life, your entire life, is very difficult.”

The 19-year-old musician — whose self-titled third album, coproduced by Geiger, will be released on Friday, May 25 — remembers learning to refer to the “For You I Will” singer by the female pronoun. “But the thing that’s amazing is that I remember the day I said ‘she,’ and it wasn’t because I said it consciously, it was because I said it without thinking, basically just in conversation,” he told EW. “I didn’t realize I did it, but she looked at me and she had the most incredible look in her eyes. If every person in the world had one of their best friends look at them that way, and express that much joy in what it meant for her to be referred to as the pronoun she is, there would no longer be an argument [over trans rights.] People would just understand.”

Mendes added: “It’s so powerful to have somebody you’re so close to go through something like that. It’s just f–king beautiful, man. I really wish you could have seen it.”

When asked if he left pronouns out of the majority of his songs because of his experience with Geiger, the “Mercy” singer responded, “Yeah, it’s true. It doesn’t matter. Everything is up for your perspective. Let it be you. It really just doesn’t matter to me at all nowadays. I love how open everybody is and how open everything is. It just makes life more fun.”

Geiger, 29, announced her transition in October 2017. “Love it or hate this is who I have been for a looooong time,” she wrote on Instagram at the time. The singer-songwriter attended her first red carpet since transitioning earlier this month.