New mum Carrie Underwood has shared her gratitude to a Good Samaritan who offered a helping hand on Sunday (31Mar19) after making a "rookie" parenting mistake.

The country superstar became a mother of two in January (19), when she and husband Mike Fisher welcomed their second son, Jacob, a little brother for their four-year-old boy Isaiah.

Carrie ventured out for lunch over the weekend with her newborn in tow, but she was left flustered after only taking minimal supplies to the restroom to give him a diaper change.

"Thanks to the nice lady who offered to buy me a drink at lunch today after I carried my naked, poo covered, screaming baby up the stairs and back to my table," the singer posted on Twitter. "It was a rookie mistake leaving the diaper bag at the table and only taking a diaper and 2 wipes. Never again."

The Jesus, Take the Wheel hitmaker's regretful incident occurred just a day after she heaped praise on her husband for helping her enjoy some extra rest.

"I wanna publicly thank the hubs for taking the kiddos and letting this tired mama sleep a couple extra hours this morning," she tweeted.

Carrie then advised her male fans and fellow parents to do the same for their other halves: "If any of you fellas out there could do this every once-in-a-while for your ladies, lemme tell you, it makes all the difference in the world!" she added.

The star will be needing all the sleep she can get in the coming weeks as she prepares to return to the road and launch her Cry Pretty Tour 360 in May (19).