Surprise – it's actually her husband, Matthew.
The actor, 42, has become somewhat unrecognizable in recent weeks since losing 30 pounds for his upcoming role in The Dallas Buyer's Club, the true story of a man with AIDS in the mid-1980s who seeks out experimental HIV drugs to prolong his life.
McConaughey looked extremely thin in photos showing him leaving a church in Austin, Texas, as he appeared to be leaning on his mother for support. If he seems as though he's somewhat ill, well, that's part of the point.
"I should not look healthy by the time I'm doing this," McConaughey told Larry King's Ora TV web series Larry King Now back in July, when he had lost 15 of the 30 pounds.
"It's a bit of a spiritual cleanse, mental cleanse," he told King. And while his pregnant wife has been facing pregnancy cravings, "[I'm] drinking a lot of tea … It takes a while for your body to understand that it has to feed off of itself and that you're not going to give it something else from the outside."
For McConaughey, who's expecting his third child with Camila, it was a major reversal from how he prepared to play a buff stripper in Magic Mike. For that role, he ate five meals a day of only protein and worked out relentlessly.