Cassy Legaspi in Japan with Darren Espanto

Cassy Legaspi is with Darren Espanto and his family in Japan.

The Espantos are there to celebrate Darren's sister Lynelle's birthday.

On Instagram, Darren shared a series of photos of them at a theme park.

"Celebrating Lynelle’s 13th at the happiest place on Earth! Happy 13th Birthday, Nenen! I can’t believe you’re a teen now. Kuya loves you so much," his caption read.

Among the snaps is a picture of the siblings with Darren's rumored girlfriend.

Meanwhile, on her social media account, Carmina Villaroel and Zoren Legaspi's daughter uploaded photos of her with Darren and Lynelle inside a certain museum in Tokyo.

For the past few months, Cassy and Darren have been often spotted together, igniting rumors they're making sweet music.

In fact, late last year, the two made headlines making public a beach getaway.