Is it permissible to leave the deceased's money for his children until they grow up, and is it permissible to spend from it on the family and develop it through projects?

The inheritance is divided as follows: The wife receives one-eighth due to the presence of children, as Allah states: "But if you have a child, then for them [the wives] is one eighth of what you leave, after any bequest you [may have] made or debt." (An-Nisa: 12). And for each of the parents, one-sixth due to the presence of children, as Allah states: "And for his parents, to each one of them is a sixth of what he left if he had a child." (An-Nisa: 11). The remainder goes to the children, with the male receiving the share of two females, as Allah states: "Allah instructs you concerning your children: for the male, what is equal to the share of two females." (An-Nisa: 11). The expenses of these children shall be covered from their own wealth if they are wealthy, and it is not permissible to take from their wealth except by right. Guardianship over the children goes to the grandfather if he is of sound judgment and capable of managing their affairs. This is the view of the Hanafis and Shafi'is, and it is the more preponderant opinion due to his compassion for his grandchildren. The grandfather may invest their wealth for their benefit and spend on them according to their needs. Finally, matters of inheritance must be referred to the Sharia courts to ensure the rights of the heirs and other interests related to the estate.