Turns out Manny Lawson and Alan Branch had a pretty good reason for missing those recent voluntary practices.

They both became dads, Lawson for the first time and Branch for the second. Both free-agent signees by the Buffalo Bills are taking part in this week’s mandatory minicamp.

“I spent a lot of that time going through that first couple weeks of trying to learn from the little one because at that point they dictate everything,” said Lawson, whose wife, Stephanie, gave birth in Scottsdale, Ariz. “What coach said to me makes a lot of sense: ‘If you’re not happy at home, you’re not going to be happy here.’ So he allowed me to go back to my family and tend to my family’s needs.”

Branch’s wife, Ashley, gave birth to the couple’s second daughter. It’s been catch-up time for both defenders since coming back to Buffalo.

“It felt good to get out there and just compete a little bit, get my hands on somebody and get back into the flow of things,” Branch said. “They put some plays in during OTAs, so I missed out on that. That and how we’re practicing, the tempo that we have, it’s kind of hard, because you can’t second-guess yourself. The ball’s going to get snapped. Just being sure of myself is the main thing I have to keep in mind.”

Defensive coordinator Mike Pettine has little doubt both Branch and Lawson will get up to speed quickly.

“It was family first,” Pettine said. “It was more important for those guys to be at home, but they’re professionals. They had their iPads. They had access to what we were doing, the practice tape, the installations. So those two guys, to me, would be the least of our worries going into training camp.”

Sweat was pouring from Branch’s bald head after Tuesday’s minicamp session. Between heavy breaths, he said the Bills are practicing faster than any team he’s ever been on.

“You can’t practice that tempo,” he said. “That’s one thing I’ve realized from this team. The tempo is different.”

Lawson, likewise, was sucking wind after practice.

“I definitely feel behind,” he said, “like my wind is not up to where it should be. But just being out here and and continuing to work out with the guys, I’m sure everything will be in its rightful place.”

For Lawson, that means with the starting unit. That’s not where he is at the moment, though, as he’s worked with the second unit in minicamp.

“It’s definitely not a position I want to be in. Anybody that’s competitive, you don’t want to be on the second team. You want to be a starter,” he said. “That’s what I’m going to strive for, getting that starting position back. You’ve got to prove everything out here. New coaching staff, and whatever you did in the past doesn’t mean anything now. You’ve got to start from scratch.”

Lawson, 6-foot-5 and 240 pounds, was the first player the Bills signed in free agency this offseason. He has started 81 of 96 career games and had 47 tackles and two sacks last season.

“Manny’s a veteran player, so we got a good chance to study him on tape,” Pettine said. “He’s a professional. We’re looking forward to taking advantage of his skill set. It’s tough for him to have not been here for the meetings and actually get those reps. I think from a conditioning standpoint given the tempo that we’re going at … he’s predictably a little bit behind where he should be, but I have full confidence that he’ll more than make that up heading into training camp.

“He’s not just one of the smartest players on the team, but one of the smartest in the NFL, so I don’t think the mental part of it’s going to be an issue for him at all.”

Branch has also been running with the reserves, bouncing between the second and third teams. The 28-year-old, 6-6, 325-pounder said Pettine’s scheme is perfect for him.

“It’s something that actually benefits me and the way I play. I’m big, I can hold a point, but at the same time, I’m not held to being in a certain spot,” he said. “That’s perfect for me. I feel like I can play all the way on the outside as a big end; I can play nose. I just got to get my head in the book and learn the rest of the calls all throughout the line and I’ll be fine. I can play any position they put me in.”

Lawson, who was looking to return to a base 3-4 defense, was sold on joining the Bills after talking with Pettine about how attacking it would be. He’s seen it in practice.

“We’re going to get after guys. We’re going to get after the offense. We’re going to get after quarterbacks. That’s what they said prior to me signing, and that’s how it’s been since I got here. They’re holding true to their word,” he said. “From the scheme that our coaches are putting together, we’re going to be a really good defense. We’re going to be a defense you’re really going to have to study on film and play hard against.”