The timing was right for Chris Pratt and Anna Faris to start a family.
A source tells Us Weekly the actors and frequent costars are "so happy" to be welcoming a son this fall. "They planned for this baby and now seemed as good of a time as ever," the source explains. "They really will be the best parents."
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"What's Your Number?" star Faris, who announced her pregnancy in May, is absolutely glowing, the source adds. "Maybe it's just her energy, but she hasn't been having trouble with the pregnancy at all!"
A second insider says Faris, 35, and Pratt, 33, "are so excited" to become first-time parents. "Having a kid is a big deal to both of them -- they didn't take this lightly."
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"Parks and Recreation" actor Pratt is also "excited to have a little guy to teach guitar," the insider adds. After his critically acclaimed performance in 2011's "Moneyball" (opposite Brad Pitt, 48), Pratt "has been into baseball again," the insider tells Us. "I'm sure he's going to sign his son up."
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Faris and Pratt met on the 2007 set of Take Me Home Tonight. They became engaged in January 2009 and married six months later in a small ceremony in Bali.
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