Ronald De Boer has told Sky Sports his brother Frank "respects Jose Mourinho a lot" after the two became embroiled in a war of words over Marcus Rashford.
Manchester United manager Mourinho called former Crystal Palace boss Frank De Boer "the worst manager in the history of the Premier League" after he said it was "a pity" Rashford is managed by Mourinho.
De Boer -- who lasted 77 days at Palace after losing four consecutive league games without his side scoring a goal -- suggested after Rashford started his first game of 2018 against Liverpool, scoring twice, that he would be better off playing under another manager.
But Ronald De Boer said his brother had been attempting to point out that Rashford's situation would be different at a different kind of club.
"Managers have different philosophies when developing young talents -- not right or wrong, simply different, and you have to respect that," he said.
"Mourinho has bought [Alexis] Sanchez and of course it's the truth that it's not good for Rashford's development and he will play less now for Man United.
"Rashford is without doubt one of the biggest talents in the Premier League and he could play a big part in Russia this summer.
"Frank respects Jose a lot and was simply pointing out that, if Rashford was playing for Ajax and had one or two bad games, he would still start the third game.
"However, he's at Man United and, after two bad games, things are different and he'd be on the bench."