Exactly!
It is often said that two can live as cheaply as one and, to a certain extent, that is true. However, it is a fact that your council tax (or whatever it's called these days) will rise by 33%. Also, bringing a Filipina to Scotland is bound to have a significant effect on the heating bills!
While Myrna is a well-respected, and senior, teacher in Panabo (Ruby was a student there while Myrna was teaching), I'm not sure that this will lead to immediate employment in the UK - she may have to set her sights a little lower in order to bring an early boost to the household income.