Jessie James Decker -- 2nd Baby Wasn't Planned ... Pleasant Surprise

It's tough to cover NY Jets receiver Eric Decker.

Apparently, it's even tougher to cover his penis ... 'cause his wife is pregnant with Baby #2 ... and she tells us the kid wasn't exactly planned.

We got country superstar Jessie James Decker out in NYC this morning ... who's due in September BTW ... and she told us a 2nd kid was always in the cards, but didn't expect it so soon!

Sort of a pleasant surprise kind of a thing.

Question is ... do you ever tell that to the kid? We asked Jessie ... she had a pretty good explanation.