The forward duo have formed the most potent partnership in the Premier League this season, combining for nine goals in just six games including the winner in Monday night's 1-0 win at Burnley.
Kane and Son have combined for 29 goals during their time together in the Premier League, second only to the former Chelsea partnership of Frank Lampard and Didier Drogba.
"It is an understanding that comes from Mauricio's time," Mourinho told reporters.
"I don't want all the credit myself, let's share with Mauricio. They play together for a long time, probably a different way because Harry is not always a nine now.
"What pleases me more about them both is that they are two top players but close friends, no jealousy, they both play for the team."