Is it obligatory to offer two sacrifices (two sheep) as an Aqiqah for the newborn over a period exceeding one year, or not? And is it permissible to combine the Aqiqah with a sacrifice of gratitude for a salary increase?

The aqiqah is a confirmed Sunnah, and it takes place on the seventh day of the child's birth. If that is not possible, then on the fourteenth or twenty-first day, otherwise whenever it becomes feasible. As for slaughtering out of gratitude for a blessing, it is permissible as long as it is not associated with a corrupt belief. It is not valid to combine the intention of the aqiqah with other intentions when slaughtering, and the intention for the aqiqah must be made at the time of slaughter.