Mr Mario Ho is shutting down talk that he had a baby with wife Ming Xi in order to get a bigger slice of the family fortune.
His father, Macau gambling tycoon Stanley Ho, 98, is not in the best of health.
Posting online over the weekend, Mr Mario Ho said the distribution of the assets had been decided a long time ago, and that he did not need more money.
A netizen, commenting earlier on the 24-year-old's posting of thanks to his wife for the birth, said Mr Mario Ho is paying tribute to her only because she has helped him get a financial windfall.
He married the Chinese supermodel, 30, in July and she gave birth to their son, Ronaldo, in October.
In his Weibo post, Mr Mario Ho said he wanted to address all the negative rumours when they surfaced in recent months but his wife advised him not to.
But he conceded that there is one "payoff" for him - he would be able to play tennis with his son in future.
He added that he had shared a game with his father, Mr Stanley Ho, by buying lighter racquets meant for kids.
His father, seated in a wheelchair in the hospital's hallway, got a fun workout.
While Mr Mario Ho, who runs his own company, is upset with the financial speculation, he might have contributed to it.
Earlier this year, he posted about his mother's wish to have a grandson, saying that he would get 100 million yuan (S$19.4 million).
While that revelation was meant to be taken light-heartedly, some netizens note that Ronaldo is the first grandson in the clan to bear the family name.
Even if Mr Mario Ho does not need more money, Mr Stanley Ho is certain to lavish his generosity on Ronaldo.
There was talk that Xi, 30, was gifted with 500 million yuan when she got married.
Mr Mario Ho, who told reporters after she gave birth that he would reward her, wants to expand his family.
"I hope to have at least three more children because I enjoyed growing up with a lot of brothers and sisters, so I want Ronaldo to have that experience too," he said, admitting that his wife may not share his enthusiasm.
While netizens may be fixated with money matters, he said in another interview that it is more important to achieve wealth through hard work.
"While our family has been wealthy for several generations, my grandfather went broke, so my father has gone from 100 to zero, and then he has worked tirelessly to take himself back from zero to 100," he noted.