The following is taken from the Book of Blessings, approved by the Congregation for Divine Worship:
(Lay persons) “may celebrate certain blessings, as indicated in the respective orders of blessings” (no.18). Examples of blessings that may be administered by lay people are the orders for the blessing of a family (no. 44), blessing of children (no.136), blessing of sons and daughters (176), blessing of engaged couples — (no.197), blessing of parents before childbirth (no.217), and so on. Some of these orders stipulate that when a priest or deacon is present, the ministry of the blessing more fittingly belongs to him (no. 176).
Please note: blessing of dogs and/or other living things or objects is NOT something a lay person can do, no matter how fancy his/her alb may be.