"抽空陪父母聊天" 的英文表达可以是 "chat with one's parents when there is free time" 或者 "make time to chat with one's parents".

关于 "抽空" 的英文表达，这个短语的来源是源于中文，在英文中可以用 "make time" 或者 "find time" 来表示。例如：

I will try to make time to chat with my parents this weekend. (我会尽量抽空这个周末和我的父母聊天。)
I know you're busy, but can you find time to call your parents? (我知道你很忙，但是能抽空给你的父母打个电话吗？)

这里还可以给出几个和 "聊天" 有关的英文表达：

chat (noun): a conversation, especially an informal one, between two or more people
talk (verb): to have a conversation with someone
conversation (noun): an informal talk involving two people or a small group of people
discuss (verb): to talk about something with someone, especially in order to make a decision or to reach an agreement

例句：

I had a nice chat with my parents on the phone last night. (我昨晚和父母通了个电话，聊得很愉快。)
Can we talk about this later? I'm not really in the mood to discuss it now. (我们能晚点再谈谈吗？我现在并不想讨论这个。)
We had a long conversation about our plans for the summer. (我们就夏天的计划聊了很久。)
Let's discuss this over lunch. (让我们在午饭时间讨论一下吧。)