A rant about the ages of the children on 9-1-1...
In 2x14 Broken (April 15, 2019) - Michael states Harry is 10 and he would have NOT already had his birthday, meaning he was born 2009 2008.
6x18 What's Your Fantasy - Bobby uses DOBs as lucky numbers - Harry's birthday is Feb 7. Based on what we learn in 9x01 Harry's birthday happens after Bobby dies so after April meaning his birthday is now July 2. It's still 2-7 just not following the US date writing rules.
Casino Week - March 20, 2025 (cross over with DO) - Athena says Harry is 17. This would now be before his birthday. That would make his year of birth 2007.
They've aged him up a year. Or probably two and forgot he had a cannon DOB. That's at least slightly more in line with the actor who is 19/20?
Also aging him up a year but probably meaning his birthday is sometime in Sept.
Same with Chris. His year of birth was listed as 2011 in Eddie Begins.
In S2E2 (Sept 2018) he's 7, but by 7x01 (March 14, 2021) Eddie says he's 13, and he turns 14 in 8x01 (Sept 26, 2024) which would make his DOB 2010
Denny comes to Hen and Karen either on the day or a day or two after the Senate votes to repeal Don't Ask Don't Tell (Flashback in 6x06) Dec 18, 2010. He is still in an infant bucket seat which makes him less than 18mo but more than 6mo because he is easily sitting up.
He has his birthday in 6x09 Red Flag (Air Date Nov 28, 2022) Karen mentions the conversation about his birth mom has been 10 years in the making. Is that from when they got him? When Eva showed up the last time? Who knows but his birthday is probably some time in Nov.
Since he wasn't a month old when he came to Hen and Karen that makes his DOB Nov 2009.
Unless they didn't mean the vote, thet meant when it went into effect (because writers are bad at dates....) which would be Sept 20, 2011, meaning he was born Nov 2010.
Mara first shows up in S7x05 You Don't Know Me (April 11, 2024) and she's 9.
She has a birthday upcoming about a week before she was taken. Now that's right around when Chris leaves. In S8E7 Hotshots (Nov 14, 2024) Chris has been gone for three months. So mid July to mid Aug is when he left. Meaning Mara's birthday is End of July to beginning of Aug 2014
Baby is the size of a mango when we see Maddie and Chim on video call in S4E1 which is either 19 or 23 weeks, depending on the specific fruit chart they were using. This is six months after the stay at home order which was March 19, 2020. So Maddie is either 19 (Due Feb 7-13) or 23 (Jan 10-Jan 16) weeks around Sept 19 2020.
Maddie is "nine and a half months pregnant" in S4E9 Blindsided when she gives birth which could mean she's 38 weeks (because technically you're due at 40 weeks or 10 months) but it could also mean that she's 42 weeks and overdue if the person assumes 9 months pregnant = baby done cooking and she'a a half month or two weeks overdue.
Dec 27-Jan 2 (38 weeks/was 23 weeks Sept 19)
Jan 24-Jan30 (42 weeks/was 23 weeks Sept 19) OR (38 weeks/was 19 weeks Sept 19)
Feb 21- Feb 27 (42 weeks/was 19 weeks Sept 19)
But seeing as a week also has 7 days, each of these could fluctuate by that much as well.
23 weeks makes the most sense seeing as S3 was supposed to end with May's grad party which would have been end of May 2020, which would make Maddie 7-8 weeks around that original party date.
Meaning Maddie was probably due Jan 10-16 and Jee was probably born Jan 24-30
Baby Bobert is even more complicated to figure out. Maddie was too early to tell people when Buck figured it out. Buck figured things out after he broke up with Tommy. Tommy and Buck got together around the Madney wedding, S7E6 (May 2, 2024). S8E5 is Halloween, Buck and Tommy go out for their 6 months anniversary in S8E6 so beginning of Nov would make sense.
S8E8 Eddie is talking to real estate agents. S8E9 he's bought a house. Needs 2-3 weeks notice to find subletter. So we're probably looking beginning of Dec he moves to Texas. Beginning of Dec was also when Maddie was kidnapped, Chimney says she's just into the second trimester (which means 13-14 weeks).
Them not being ready to tell people around beginning of Nov when she was 11ish weeks makes sense. In the hospital after Chim says they're having a boy. Earliest ultrasounds would be 14 weeks, although medical standard is still 18-20 weeks. They probably told Chimney early to give him some positive news given the circumstances.
Maddie would be due roughly May 16 - May22 with Bobert.
Bobby's funeral was a week after they had alredy waited two weeks so after May 8th. So no wonder Chimney's breakdown was really badly timed.
Harry's DOB is Feb 7, 2007/08
Mara is end July/ mid Aug 2014