O regulamento é explicado nos Site da Embaixada da Finlândia no Reino Unido :
According to the EU Directive 38/2004 (Art. 2) family members of EEA nationals who are in possession of a British residence permit named "Residence Card of a Family Member of an EEA National" do not need a visa for visits up to 90 days in the Schengen area if they are joining or travelling with the EEA national. Residence card should be endorsed in your valid passport.
Portanto, se sua esposa e filha tiverem o cartão de residência do Reino Unido, elas poderão visitar sem visto.