From the Washington Post article on the proposed legislation:
Currently, federal employees are eligible for 12 weeks of unpaid parental leave and can substitute paid sick and annual leave for part or all that unpaid time. Agencies additionally may advance leave for those purposes to employees who have accumulated an insufficient amount; the memo essentially removed the discretion they had over whether to grant such requests.
Federal employees receive 13 days of sick leave a year with no limit on how much they can build up. They also get between 13 and 26 days of annual leave per year, depending on their length of service, but generally can carry no more than 30 days of it from one year to the next. Advanced leave amounts to borrowing against leave to be earned in the future.The momentum for such legislation in the private sector is still dim, if not non-existent. This is at least an admirable step in Congress.