Blue Bloods star Donnie Wahlberg‘s secret mistress has dropped a bombshell – she’s pregnant!

Gorgeous Canadian model Michelle Tomlinson – who broke up the New Kids on the Block hunk’s nine-year marriage to Kim Fey – is due to give birth to his love child in March, say pals.

Donnie, who stars in the new CBS cop show Blue Bloods, isn’t exactly thrilled with the news.

He "freaked out" and dumped the 27-year-old stunner when she told him she was expecting his baby, sources say.

"He told her then and there it was over," a source said.

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