Is someone who marries his deceased brother's widow to raise his brother's orphaned children considered a guardian of orphans, even though family members assist him with expenses, and what is his reward from Allah?

"The one who strives to support the widow and the poor, and the one who sponsors an orphan, will receive a great reward. Texts have indicated that striving to support widows and sponsoring orphans are among the most excellent acts of drawing near to Allah and the best acts of worship. In the Hadith, 'I and the sponsor of an orphan will be in Paradise like this,' and he gestured with his index and middle fingers. The one who participates in an act of obedience is a participant in its reward. The reward of one may be greater than the other, depending on their effort and contribution."