The Kapamilya actor shared a photo of himself and Aki on Instagram when they last met.
The 11-year old flew to the USA with Paulo's ex partner LJ Reyes last August.
"This was before he went. Paulo shared that he had a PC built for him (his) birthday and that he was thrilled about it.
The actor shared the picture after a fan requested it during an Instagram Q and A session.
Paulo wrote Aki a sweet message to celebrate his 11th birthday, calling him his "forever child".
"I would give anything to spend more time with my family and be there for you as you grow up." I love you forever," said Paulo.
Paulo also gave Aki his Best Actor Award at the 2020 Metro Manila Film Festival.
LJ and Paulo split in 2013 and decided to co-parent their son.