Pete Wentz completely panicked when wife Ashlee Simpson went into labour.
The singer gave birth to son Bronx Mowgli Wentz last week.
But Pete, 29, was so overwhelmed he was having palpitations.
‘Right before she went into labour, I was like, “Oh my God, I think I'm having a heart attack!”’ he recalls.
‘Natural things start going on in your body. My heart started beating really fast.
'You see your wife in all this pain, and you really don't know what's happening.’
Fortunately, Ashlee, 24, kept calm.
‘[She] took care of me and made sure I was okay and then we went into labour,’ he told Ryan Seacrest's KIIS-FM radio show. 'That's why she's a saint.'
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