Steven Tyler, 71, is joined by girlfriend Aimee Preston, 32, for 'Ad Astra' premiere

There's a forty-year age difference between them, but Steven Tyler and his girlfriend are going strong.

The Aerosmith frontman, 71, had Aimee Preston, 32, by his side Wednesday at the premiere of "Ad Astra," the two opting to share a few kisses for the cameras. His daughter Liv Tyler, 42, stars in the drama-fantasy film.

The May-December couple became close several years ago when Preston began working as Tyler's personal assistant. They went public with their relationship three years ago, in 2016, but reports of a relationship first surfaced as early as 2014.

The rocker's daughter Chelsea was also in attendance, and she was all smiles as she posed for photos with her husband, her father and his girlfriend. The 30-year-old also showed off a baby bump, revealing she's due in February.

Although Tyler's girlfriend may be young, she has quite a resumé: Upon first graduating from college, she worked for the Trump family as a personal assistant within the Trump Organization. She also used to work as Victoria Beckham's assistant, but she was reportedly let go.

Also looking sharp at the "Ad Astra" premiere was Brad Pitt, who co-stars alongside Liv Tyler. The movie is out in theaters Sept. 20.