Novios

Plural nouns in Spanish are often grammatically gendered but semantically mixed. With this in mind, let's look at the common-sense interpretation of words like novios, padres and tíos.

• Novios: boyfriend and girlfriend. Peleas de novios = arguments between a boyfriend and a girlfriend. It's true that the word novios could refer to a gay male couple, but without context, that's not the first image that would come to mind for native speakers. In a wedding context, los novios means 'the bride and groom'.
• Hermanos: brothers and sisters. If you ask someone how many hermanos they have, they will normally include males and females in the count. To be more specific, words like varones, males, will be used. Somos hermanos could mean either 'We're brothers' or 'We're brother and sister'. The point to absorb here is that hermanos can refer to male siblings only but is usually doesn't. By contrast, hermanas necessarily refers only to sisters.
• Padres: parents. The stock expression los padres de familia doesn't refer to 'fathers'; it is a standard expression used by schools to refer to the parents, both mothers and fathers, of their students. Remember that the cognate parientes means 'relatives' in general, not specifically 'parents'.
• Tíos: aunt and uncle. Voy con mis tíos would usually mean I'm going to my aunt and uncle's house. It's possible, of course, that mis tíos refers to your uncles, but that's a less common situation.
• Sobrinos: nieces and nephews. The word sobrinos does not conjure up 'nephews but not nieces' unless the context dictates that interpretation.

Be grateful that as an English-speaking student of Spanish you're going from a two-word / two-meaning situation to a one-word / two-meaning situation and not vice versa. It's harder for native Spanish speakers to accept that English requires awkward constructions like my aunt and uncle instead of offering a specific word that refers to the couple.

Todas y todos

In public speech, constructions like todas y todos and are increasingly heard as a replacement for the standard form, todos. This practice apparently started as rhetorical move by politicians to be inclusive. So far I have not heard these forms in spontaneous speech, only in speechmaking, advertising, entertainment and the media.

Niñ@s

In copywriting you'll sometimes see the at-sign @ used as a shorthand to emphasize gender inclusivity. Traductor@s = male and female translators, traductoras y traductores. In social media, x is also seen with the same purpose: niñxs.