Returning only the first child record in a one-to-many join

I rarely do SQL so forgive me for this newbe question.  A user has two
tables in a one-to-many relationship.  The user would like to join the
two tables but only returning the one record from the child (many)
table for each record in the parent.

Example, we have a nest site table.  One a  times a year a biologist
goes out and surveys bald eagles eggs or young.  Counts of the bald
eagle eggs/young are held in an observation table.  We want to show
most recent survey date for each nest site.