Toy giant Mattel Inc. is preparing to take over the bankrupt manufacturer of Nabi children's tablets after winning a bankruptcy auction earlier this week with a $21.5 million bid, Dow Jones Daily Bankruptcy Review reported today. Court papers show Mattel put in the highest offer for the brand of colorful tablets made by Fuhu Inc., which went up for sale after the El Segundo, Calif., company filed for bankruptcy in December. Fuhu has sold more than 4 million tablets through retailers like Target, Best Buy and Toys R Us but struggled after delays at the toy's overseas manufacturer caused it to miss much of the 2014 holiday sales season.