Mr Cameron said he would like to have more children
David Cameron has spoken of the "immense void" left by the death of his son Ivan earlier this year.
The Tory leader told Grazia magazine "so much of his life had been arranged" around six-year old Ivan, who suffered from cerebral palsy and epilepsy.
Mr Cameron, who has two other children, said he would like to have more.
He also praised his wife Samantha, saying she gave him valuable advice and told him when he was using language the public would not relate to.
Ivan Cameron, who needed round-the-clock care, died in February.
Mr Cameron told Grazia: "So much of our life was arranged around Ivan, the void is immense.
"But also, you are suddenly able to do things you couldn't do before, like walk across a muddy field perhaps and you find yourself there quickly and it's like 'oh here we are' followed by a feeling of guilt because you're having a good time and he's not there."
Mr Cameron said he would "certainly" like to have more children but he would have to "wait and see" whether that happened.
He also gave an insight into the role that his wife Samantha played in grounding his politics.
He admitted she would rather stay at home watching television than attending political functions.
However, he added that she frequently advised him on how he communicated with the public.
"She's interested in politics but sometimes politicians have their own language and she cures me of that regularly.
"She will say 'if you put it like that, no-one will have a clue what you're on about'."
Referring to his teenage years - most of which were spent at Eton - Mr Cameron said he had flirted with trouble.
"When I was 14, 15, 16, I was doing things that teenagers do in terms of drinking too much, being caught having the odd fag, things like that.
"I didn't do particularly well in my O-levels but I was fortunate enough that 16 was a turning point for me.
"I was, in some ways, heading in the wrong direction and I pulled myself up and headed in the right one."