Yeah, in Polish it's the same. You can use "swój", "swoja" and "swoje" whenever you feel like it. So "Vi älskar våra barn" can be both "Kochamy nasze dzieci" and "Kochamy swoje dzieci" (though to me it sounds like the latter is emphasising that it is our children that we love).
Tricia, so-called "ett" words are words of neuter gender. We call them "ett" words because in situations where en or ett are required, they take ett.
However, en words and ett words can also be used without any en or ett in front of them. We still call them en/ett words because it's faster and simpler than talking about "words of common gender" or "words of neuter gender."
Adia, you do not need Duo to learn the meanings of particular words. For that, you can use, for example, an online swedish-english dictionary. Here is a link to one: https://www.google.com/search?q=swedish+english+dictionary&oq=swedish-english&aqs=chrome.2.69i57j0l5.6683j0j8&sourceid=chrome&ie=UTF-8
By the way, the Swedish word for "cancer" is "cancer". It is an en word.
We love our child = Vi älskar vårt barn.
We love our children = Vi älskar våra barn.
Do you see how it works? The word "barn" is the same in both singular and plural. That is, it can mean either "child" or "children". But in a Swedish sentence, the ending of "vårt" vs. "våra" tells you whether singular or plural is meant.
If the noun involved is common gender rather than neuter, then the choice is between "vår" (singular) and "våra" (plural):
We love our dog = Vi älskar vår hund
We love our dogs = Vi älskar våra hundar
We love our vacuum cleaner = Vi älskar vår dammsugare
We love our vacuum cleaners = Vi älskar våra dammsugare