Kelly Clarkson Preparing to Be a Bride…and a Stepmom

Now that Kelly Clarkson is engaged to her boyfriend Brandon Blackstock, she not only has to prepare to be a wife, she has to get ready to be a stepmother.  But sources say that she's working on it.

An insider tells the magazine that Kelly "pays special attention" to 11-year-old Savannahand seven-year-old Seth, Brandon's kids from his first marriage to ex-wife Melissa.   For example, the insider says that Kelly took the kids on a VIP tour of Disneyland last summer when she was on a break from shooting her ABC music competition show Duets.

However, like all aspiring stepmoms, Kelly is "careful not to step on their mother's toes," says another insider.  Kelly also would "definitely" like to have her own kids with Brandon, dishes the source.

So far, Kelly and Brandon have not set a wedding date, but a friend tells Us Weekly that the original American Idol champ "wants to go all-out," just like her friends Blake Shelton and Miranda Lambert did when they wed in front of 550 guests in Texas in 2011.  But don't expect anything too over-the-top -- the friend says Kelly will "keep it country."